Yep, SpinToWin is spot on. But really, you have so many options to try. First suggestion, copoly to copoly hybrid. How about Volkl Cyclone (17 or even 16) in the mains, then Volkl Cyclone Tour (17) in the crosses...one, the string bed will soften up and long as you are smart about you tension. You should not lose much at all in the performance department and you may even pick up some. But keep the changes logical, creative and in steps of / changes of one! Record your results.
From my experience, if I had a sync gut or multi into the string bed with a copoly, I prefer the copoly to be a round string. Because the copoly is the domain string, the round will create less havoc on the others (sync/multi).
If you go with a sync, I find you have to crank the tension up a bit to miniumize string movement, power..pulling it the some control...yet still keeps the string bed soft. For syncs, if you go that route. I recommend a good mono filament sync.
make it fun.....I know you will nail it...